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					         Maligaya High School
      Ilang-ilang St., Maligaya Park Subd.
              Brgy. Pasong Putik,
                  Quezon City




Environmental Pollution Caused by Heat Engines




              A Project Submitted

            As Partial Fulfillment of

             The Requirements in

                    Physics




                 Submitted by:

           Diane Rose Ann Lagrama



                   IV-Rizal
               January 14, 2010



                 Submitted to:

            Mr. Geronimo Fiedalan
                                                                                                  2


HEAT ENGINE
Performs the conversion of heat energy to mechanical work by
exploiting the temperature gradient between a hot "source" and a
cold "sink". Heat is transferred to the sink from the source, and in
this process some of the heat is converted into work.


Examples of Heat Engine:                                                    Heat Engine Diagram

                           a) steam engine - a heat engine that performs mechanical work using
                                         steam as its working fluid.

                           b) diesel engine – an internal combustion engine
            A                            that uses the heat of compression
                                         to initiate ignition to bum the fuel.

                           c) petrol engine – an internal combustion engine              B
                                         w/ spark-ignition, designed to run
                                         on gasoline and similar volatile fuels.


            C              d) stirling engine – operates by cyclic compres-
                                         sion and expansion of air or other
                                         gas.

                            e) drinking bird toy – a toy heat engine that                D
                                         mimic the motions of a bird drinking
                                         from a fountain or other water source.

                           f) heat pump – a machine or device that moves
            E
                                       heat from one location to another
                                       location.

                       g) refrigerator – transfer heat from it to the
                                                                                          F
                                         external environment, cooling the
                                         contents to a temperature below ambient.

M                       h) gas turbines – extracts energy from a flow of
                                          Combustion gas.




                      Environmental Problems Involving Heat Engines                       H
        G
                                                                                          3

   Three sources of emittants from engine:
                 A. Fuel tank emit fuel vapours
                 B. Crankcase gives out the partly burnt air-fuel mixture blown off through
                    the piston rings
                 C. Exhaust pipe

   Pollutants from incomplete combustion:
                  A. gaseous
                        1. Unburnt hydrocarbons (UHC)
                        2. Carbon monoxide (CO)
                        3. Nitrogen Oxides (NOx)
                  B. particulates
                        1. Soot particles
                        2. Soluble organic fraction

   Thermal Pollution
         Usually associated with increases of water temperatures in a stream, lake, or ocean
         due to the discharge of heated water from industrial processes, such as the
         generation of electricity. Increases in ambient water temperature also occur in
         streams where shading vegetation along the banks is removed or where sediments
         have made the water more turbid. Both of these effects allow more energy from the
         sun to be absorbed by the water and thereby increase its temperature. There are
         also situations in which the effects of colder-than-normal water temperature may
         be
         Observed.

   Small chronic changes in temperature can also
    adversely affect the reproductive systems of these
    organisms and also make them more susceptible to
    disease. Cold water contains more oxygen than hot
    water so increases in temperature also decrease the
    oxygen-carrying capacity of water.




   Car Exhaust Pollution
                                                                                             4
       The personal automobile is the single greatest polluter, as emissions from a billion
       vehicles on the road add up to a planet-wide problem. Driving a private car is a typical
       citizen's most air polluting activity. The negative effects of automotive emissions are
       maximum when you sit in traffic surrounded by cars, their engines idling. Everyone in a
       traffic jam is getting poisoned.

       The Combustion Process, Gasoline and diesel fuels are mixtures
       of hydrocarbons-made of hydrogen, oxygen and carbon atoms)
       Hydrocarbons are burned by combining with oxygen. Nitrogen
       and sulphur atoms are also present and combine with oxygen
       when burned to produce gases. Automotive engines emit
       several types of pollutants.

   Marine Engine Pollution
      Fuel from outboard motors in the primary cause of Federal
      impaired water body designations. Most boaters are aware
      that engine emissions can produce ground-level ozone and
      smog. Ozone is a recognized respiratory system irritant that
      causes lung and heart inflammation. Products of combustion
      include the greenhouse gases carbon dioxide (CO2) and carbon monoxide (CO). Carbon
      dioxide is seen as a major contributor to global warming.

   Flue Gas
       It is discharged into the atmosphere trough an exhaust pipe, flue gas stack or
       propelling nozzle. In spark-ignition engines exhaust gas from an internal
       combustion engine whose fuel includes nitro methane, contains nitric acid vapor,
       which when inhaled causes a muscular reaction making it impossible to breathe,
       and people exposed to it should wear a gas mask. They produce smaller quantities
       of toxic pollutants than petrol and diesel engines of the same power.

				
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posted:9/26/2010
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